


I’ve Got a Secret You Can’t Keep

by blarfshnorgull



Category: Fire Emblem: Fuukasetsugetsu | Fire Emblem: Three Houses
Genre: Alternate Universe - Modern Setting, Comedy, F/F, F/M, Humor, Lysithea and Annette are mentioned briefly but don’t show up, M/M, Pre-Relationship, mentioned minor relationships - Freeform
Language: English
Status: Completed
Published: 2020-05-09
Updated: 2020-05-09
Packaged: 2021-03-03 02:14:09
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,925
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24087184
Author URL: https://archiveofourown.org/users/blarfshnorgull/pseuds/blarfshnorgull
Summary: Felix thinks Sylvain’s girlfriend is cheating on him.Dimitri thinks Felix needs more evidence.Sylvain doesn’t think.
Relationships: Dimitri Alexandre Blaiddyd/Felix Hugo Fraldarius, Dorothea Arnault/Ingrid Brandl Galatea, Dorothea Arnault/Ingrid Brandl Galatea/Sylvain Jose Gautier, Dorothea Arnault/Sylvain Jose Gautier, Ingrid Brandl Galatea/Sylvain Jose Gautier
Comments: 13
Kudos: 46





	I’ve Got a Secret You Can’t Keep

**Author's Note:**

> Apparently I’m a one trick pony and decided to write another modern au dimilix fic where I focus on Felix suffering for comedy ¯\\_(ツ)_/¯

Felix’s day is already off to a weird start.

The last place he wants to be is in some artisanal bakery masquerading as a coffee shop, yet here he is. He blames his inability to say no to Annette. And the fact that Lysithea and Mercedes were there to tag in when Annette’s puppy eyes stop working.

Not that they needed to. He’s always weak for Annette, and he hates it; her girlfriend and best friend are just the icing on the guilt trip cake.

And now he’s ordering three unicorn hot chocolates.

And a cupcake, because Lysithea.

Felix watches the barista pour the _very_ pink drink into the far-too large cups, and he swears he can feel cavities forming. Then the poor soul behind the counter crams an unholy, multi-color amalgam of whip cream, sprinkles, and marshmallows into the terrifyingly pink liquid. 

Can you get diabetes from proximity alone? Maybe he should call a doctor to double check.

The barista places the nightmare drinks on the counter, along with a vanilla cupcake that has no right to look so ominous. Felix pities Lysithea’s dentist.

Maybe he shouldn’t be enabling her sugar habit. Maybe he shouldn’t have agreed to getting the drinks in the first place. Maybe he shouldn’t be dissociating in the bakery that’s pretending to be a coffee shop while he tries to cope with the fact that he’s the middleman for three women rotting their teeth. 

Maybe he shouldn’t be doing a lot of things.

“Sir, you’re holding up the line.”

Oh, right. He has to actually take them these abominations now. 

Felix grabs said abominations off the counter and begins shuffling out of the worst place in the world. Except, a painfully familiar laugh interrupts his retreat. Goddess help him, it can’t be anyone other than Dorothea.

Felix whips his head around to find the source of the offending noise. If he accidentally runs into Dorothea and Sylvain on a date, _here_ of all places, then it’s officially the nightmare scenario. In fact, he’s had this exact nightmare before, just less pastel. 

Sure enough, he spots Dorothea sitting in the corner of the shop. He can’t see who exactly she’s sitting with, other than they’re too short and too blonde to be Sylvain. Thank the goddess for small mercies, he wouldn’t be able to handle —

Dorothea leans in and kisses the blonde stranger.

Felix drops the drinks. 

They splatter like a pastel murder scene, drenching the customers that weren’t out of his immediate vicinity. They give a shriek, and the barista calls out to him. Every eye is on him, and Felix does what any reasonable person would do in this exact scenario.

He bolts.

He barrels out the door before Dorothea can so much as even _think_ about looking in his direction. And he’s calling Dimitri at the same time. It’s basically a panic response for Felix at this point.

“Felix —”

“Dorothea is cheating on Sylvain.” Whatever the fuck Dimitri was going to say gets cut off by Felix’s bout of furious panic. Yeah, he’s impatient; he knows it.

Dimitri goes dead silent while Felix is still continuing his mad dash away from the bakery of horrors. Maybe he should’ve eased Dimitri into the topic? Actually, small talk would probably make him more concerned. This is definitely the best approach.

Felix hears a deep inhale on the side of the line. Good to know that Dimitri isn’t dead, just rebooting. 

“Felix, that’s a very serious accusation. Are you sure?”

“Yes!” Felix defends himself empathetically. “I didn’t see it clearly, but I know what was happening!”

There’s another pause before Dimitri finally answers him. “We need to confirm before we tell Sylvain,” Dimitri responds slowly. Almost like he’s talking to a child. Or maybe a trauma victim.

“I already have a plan.”

  
  


—

  
  


“This isn’t exactly what I thought your plan would be,” Dimitri grumbles. He’s doing his damndest to make himself as small as possible, not that it’s even remotely effective. He’s a giant, and no amount of meek crouching behind a bush will change that.

Speaking of, the fact that there’s such a weirdly huge bush in the park is quite the unexpected boon. This is the park that Dorothea visits every Thursday, why she visits it Felix has no idea, just that Sylvain mentioned it before. A dedicated schedule means one thing: snooping. He’s not proud of it, but if there’s any chance to catch Dorothea in the act, short of following her every move, this was it.

So, now he’s here, holed up with Dimitri, waiting to strike. After all, what are friends for?

 _Just_ friends. Which is a choice. Felix definitely isn’t scared to confess to Dimitri or anything like that.

“Just shut up and take the binoculars.”

Dimitri, ever the pushover, takes the binoculars with barely more than a defeated sigh. But instead of actually using them, he just stares at them and frowns. _Really_ frowns. If Felix were being generous, he might describe it as adorable. But he’s not generous. And Dimitri isn’t adorable.

Felix totally isn’t distracted.

Dimitri, completely ignorant to Felix’s internal monologue, continues the conversation like a normal person, “What do I even say when someone asks what we’re doing?” His sentence is more of a grumble than a question, and definitely isn’t endearing at all. Nor is the way his brow scrunches when he glares at the binoculars like he wants them to disintegrate.

Definitely not endearing. Felix is _completely_ focused.

“Bird watching, obviously,” Felix scoffs like it’s not a totally absurd answer.

No one is going to believe that, and Dimitri probably knows it.

“No one is going to believe that.”

Props to Dimitri for not being totally naive. Unfortunately, that means Felix needs to double down on the fact that his plan isn’t paper thin and kind of shitty. He didn’t exactly come with a backup plan, but Dimitri doesn’t need to know that. Especially since he was already giving Felix grief for jumping to conclusions.

“Sure they will.”

“Felix, we look far too suspicious for bird watching.”

He has a solid point. Two grown men who huddled in a bush while staring at women through binoculars looked _really_ suspicious. But Felix isn’t going to admit that this might be a bad idea, so Dimitri is just going to have to deal with this.

“What, are you afraid that being a huge guy with an eyepatch makes you too identifiable?”

Dimitri turns to look at Felix, incredulous. “Yes, actually.”

Felix is about to bite out a retort, only to notice a brunette woman enter the park and situate herself on a bench. A brunette woman with _a lot_ of cleavage.

Felix smacks Dimitri’s shoulder to get his attention on her. “I think that’s Dorothea.”

Dimitri turns his attention off Felix and onto probably-Dorothea. He squints in concentration and Felix suddenly wonders if squinting helps when you only have one eye. Despite his earlier complaints, Dimitri brings the binoculars to his eye to survey the scene.

A blonde blob approaches the bench and sits next to definitely-Dorothea.

The anticipation might as well be a murder weapon.

“What are they doing?” Felix hisses in Dimitri’s ear.

Dimitri swats Felix away. “I’m looking! I’m looking!”

The two vaguely-people on the bench are quite close, too close to be casual, and Felix _needs_ answers now. Why did he ever think giving the man with one eye the binoculars was a smart decision?

Dimitri freezes.

Felix sighs in resignation. Dimitri’s response is all he needs. Some distant corner of his mind hoped he was mistaken the other day, but he knows what he saw. It's a damn shame. Felix has never seen Sylvain so attached to another woman in his life, and she has the gall to cheat on him with—

“Felix, I think… I think that might be Ingrid.”

“WHAT!?”

Felix rips the binoculars out of Dimitri’s giant hands, no longer caring how much of a scene he will make. Dimitri crashes down with a yelp like a shitzu. No man that large should be capable of making a sound like that, yet Dimitri is always surprising him.

Felix looks at the blonde, _really_ looks at her. Coming face to face with her feels like a fucking drop kick. _Ingrid_ is sidled up next to Dorothea in a way that can’t be anything other than romantic. They’re practically nestled together. Like Sylvain doesn’t mean shit to either of them.

Felix drops the binoculars and storms away.

“Felix, wait!”

Felix ignores Dimitri’s plea and keeps pushing forward. He can’t even think about what he just witnessed; he needs to get as far away as he possibly can before he explodes.

But for as fast as Felix is, he’s no match for the, quite frankly, ridiculous strides that Dimitri makes on his giant legs. Felix has always lamented not inheriting his father’s height, and right now just proves how unfair their height difference is. How the hell is he supposed to dramatically storm off if Dimitri continues to outstride him?

Dimitri’s hand latches onto Felix’s upper arm. Fucking perfect. Not only does Dimitri have stupidly long legs, he has an exceptionally firm grip that would put a steel trap to shame.

Not that Felix has ever paid special attention to Dimitri’s grip before or anything.

“Let me go!” Felix is aware he sounds like a petulant child, but this has never stopped him before in his entire life.

Dimitri tightens his grip on Felix. “No. I know what you’re planning.”

“Like hell you do.”

Dimitri quirks an eyebrow at that. “So you’re not going to run off and tell Sylvain immediately?”

_Shit._

Dimitri sighs as soon as Felix freezes in his grip. “Felix, I mean no disrespect, but you are not… the most tactful person.” Felix bristles at the completely-true statement, but Dimitri ignores the lit fuse and continues gently. “Please let me handle this.”

Felix makes the horrible mistake of looking at Dimitri. He looks so sincere with his stupid eye that definitely has never made Felix go weak in knees. That’s definitely not what’s happening right now. He is a pillar of strength, and Dimitri will _not_ sway him.

“Felix, please,” Dimitri says quietly.

_Fuck._

“Fine. _You_ handle it.”

  
  


—

  
  


If Felix knew that Dimitri’s idea of “handling it” involved inviting Sylvain, Dorothea, and Ingrid over, he never would have agreed to it. Especially since they were playing fucking Scrabble. 

They don’t even like Scrabble!

But Felix agreed to let Dimitri handle it, and if that means keeping his mouth shut, he’ll say nothing. But he will glare; by the goddess he will glare his heart out.

Not that anyone notices, since glaring is Felix’s default expression. Or maybe they were too wrapped up in their game. Felix doubts this because Sylvain is crushing them, but Felix also doesn’t play Scrabble because he’s not a chump. Maybe scrabble just requires a lot of attention, so much attention that apparently Dimitri forgot what the fuck he should be doing.

Like he forgot that he gathered them all together to talk about the fact that Dorothea and Ingrid are backstabbing liars.

But no, Dimitri is playing Scrabble with them instead of confronting them.

It’s a very Dimitri thing to do, but goddess, Felix wants to strangle him. Being forced to sit and play nice with Dorothea and Ingrid after what they witnessed feels like actual hell. Especially since he agreed to sit and be quiet for Dimitri, which already goes against Felix’s natural instinct.

Dorothea’s phone rings. She looks down at the offending noise and makes an annoyed face. “Sorry, I have to take this. I’ll be right back.”

She steps up from her seat on the couch between Sylvain and Ingrid, and walks out of the room hurriedly. Good riddance. Felix knows Dimitri means well, but he’s lost patience ages ago. Once the sound of Dorothea’s heels fades, Felix seizes his opportunity. 

“Syl— ” Felix doesn’t even get the chance before Sylvain interrupts him. 

“Thanks for inviting Dorothea.” 

Felix feels sick. Sylvain sounds so serious, so _happy._ Never once like how he was with any girl before. 

“I know it’s weird inviting people that you all aren’t that close to, but I really appreciate it.” Sylvain looks down, almost _shy._ It’s so jarring that Felix almost forgets that the girl that’s making him feel this way is cheating on him. “Seriously, thank you for trying to include her.”

Dimitri goes soft, and he smiles bittersweetly at Sylvain. “Of course we’d include her.”

The puzzle pieces for Dimitri’s behavior finally slot into place. Felix feels like an idiot for expecting Dimitri to be blunt about the situation. He’s always been a bleeding heart that can’t stand to see anyone get hurt, Felix _knows_ this, and yet he still didn’t understand. He’s stalling because he doesn’t want to hurt Sylvain.

Ingrid nods in agreement. “We know she means a lot to you.”

Felix has never hated Ingrid more in his entire life. But he bites his tongue for once in his life. He gets it; Dimitri doesn’t want to cause any more harm than necessary, and he almost forgets his promise in a fit of impatience.

He hears the click of Dorothea’s heels as she makes her way back towards them. Every click is like a bludgeon against Felix’s nerves, working away at his resolve to leave the situation to Dimitri. He takes a deep breath.

_You can do this, you promised Dimitri._

Dorothea enters the room, walking right past Sylvain and making a beeline for Ingrid. She settles in next to Ingrid, practically _cuddling_ they’re so close, all right in front of her actual boyfriend. Felix clenches his fist to keep from making a scene. It’s hardly working, but he’s hanging by a thread, and he needs to latch onto something to keep himself sane.

Ingrid readjusts herself to be closer to Dorothea. 

Felix sees red.

“Dorothea is cheating on you with Ingrid!”

He lasted ten seconds.

Ingrid leaps away from Dorothea, putting as much space between the two of them as possible. She might as well have screamed her guilt for the world to hear with how obvious she was being.

Dimitri turns to Sylvain, raising his hands in a placating motion. “Sylvain, I am so sorry. We only found out recently and we didn’t know how to break the news to you.” Dimitri bows his head a bit as he continues, “I am so sorry that I hid this from you.”

Sylvain merely looks over at Dorothea, who looks unfazed by Felix’s accusation. Way too calm for a lying liar that was caught cheating. She should be more like Ingrid, curled up in a ball of shame on the other end of the couch.

She quirks an eyebrow at Sylvain but says nothing otherwise, and Felix decides that murder might be worth it.

Dorothea lets out a defeated sigh. “Felix, sweetie, maybe you should stay out of things that don’t concern you,” she says in that vile and saccharine tone that Felix _hates._ Especially now.

Felix’s blood _boils._ “You’re cheating on my friend! How —”

“We’re having a threesome!” Sylvain shouts, murdering Felix’s train of thought.

What.

Dimitri’s face twists as if he just smelled something awful. Or heard the weirdest shit possible. “Wh—”

“WHAT!?”

Sylvain sighs and raises his hands in mock surrender. “Look, Felix—”

Unfortunately for Sylvain, Felix doesn’t give a shit about what he’s going to say. Instead he’s locked on the ball of shame formerly known as Ingrid.

“You’re sleeping with Sylvain? _Willingly?”_

Sylvain’s hands fall, and his expression contorts into something confused. “Hey, wait a second—”

Ingrid makes a noise like a dying cat.

Felix looks back at Sylvain and states the obvious. “I just thought she had standards.”

Sylvain’s face twists in offense. “What the fuck, Felix?”

“Well, Dorothea is there too…” Dimitri mumbles as if it was more of a half-thought.

“You too, Dimitri!?” Sylvain shrieks indignantly.

Dimitri’s eye widens comically as he realizes what he said. “I did not mean to imply—”

Sylvain shoots up and points aggressively at the space between Felix and Dimitri. “You know, I actually slept with Ingrid way before I even met Dorothea!”

Nausea roils in Felix’s stomach. “That’s disgusting!”

Sylvain flares up again. “WHAT THE FUCK, FELIX—”

Dorothea bursts into laughter. “As hilarious as this is, I think we’ve embarrassed Ingrid enough for one night.”

They all look over at Ingrid, still a compact ball of shame. _Definitely_ dying from humiliation.

Dorothea reaches her hand out towards Ingrid, and she takes it without looking. Dorothea pulls Ingrid to her feet and drags her to the door with her. “Come on, Sylvain, we’re leaving.” She turns her attention towards Dimitri, “Thank you for inviting us over. It… well, it was a night.”

Sylvain gets up and follows his girlfriend — _girlfriends_ — to the door. He opens it for them, ushering them out the door like the world’s worst gentleman. He turns on his heel to leave but stops halfway through the door.

“Before the two of you say anything about our relationship,” Sylvain steps further out the door, only keeping a sliver opened as he calls back to them, “Why don’t the two of you work _your_ thing out first? I’m sick of this pining shit from both of you.”

Dimitri sputters uselessly, and Felix throws the scrabble board at him.

Uncomfortable silence spreads as soon as the door slams shut.

“Felix, if I may —”

“Just shut up and kiss me.”

Dimitri happily obliges.

**Author's Note:**

> I’m just saying, the fandom hasn’t capitalized on Dorothea/Ingrid/Sylvain as an OT3 and I’m extremely disappointed.
> 
> Also big shout out to my betas Abby and Ari for keeping my fics comprehensible. I love them and would die for them lmao.


End file.
